The present invention relates generally to window roller blinds or partition nets, and particularly, to roller blinds and partition nets adapted for installation into automobiles.
A rear-window roller blind, which operates without any guides, is known from EP 0 240 747. A spring-biased winding shaft of the rear-window roller blind is rotatably seated in a case provided on or below the rear window shelf. The blind strip is mounted on the winding shaft at one of its edges, while its other edge, parallel to the first edge, is connected with a pull rod. The pull rod simultaneously serves to stiffen the respective edge of the blind strip.
For spreading out the blind strip, and keeping it in spread-out condition, two pivot levers are seated in the winding shaft. The free ends of the two rigid pivot levers are in sliding engagement with the pull rod. By pivoting the pivot levers in opposite directions, the blind strip is pulled off the winding shaft and is spread out against the action of a spring. At the same time, the pivot levers carry the respective edge of the blind strip in any operating condition and cooperate with the spring-biased winding shaft to keep the blind strip in spread-out condition.
Pivoting of the levers is effected via a crank gear. The levers are extended for this purpose beyond the pivoting axes, and the extension serves as crank for engagement of a pull rod. The other end of each of the two pull rods is likewise connected with a crank, and these cranks rotate with the output shaft of a gear unit.
With such an arrangement, a geared motor must be arranged approximately midway between the two pivot levers. This, in connection with the crank arms, results in considerable space requirements in an undesirable location of the vehicle, namely in the middle of the luggage compartment below the rear-window shelf.
It is an object of the present invention to provide a window roller blind or partition particularly adapted for installation adjacent a rear window of tin automobile, which has an actuating mechanism that is more compact in design and which does: not substantially interfere with usable space in the vehicle.
Another object is to provide a rear-window roller blind or a partition net as characterized above which has actuating elements driven without the use of any cranks.
In carrying out the invention, whether the device is configured as a rear-window window roller blind or as a partition net, two actuating elements are provided which have one of their ends seated on the output shaft of an angular gear. The angular gear can have smaller dimensions than the cranks so that considerable space savings can be realized. The input shafts of the angular gears extend parallel to the axis of the winding shaft and can be easily coupled by a drive shaft, including a flexible shaft.
Alternatively, each gear unit may be provided with a separate motor. Special synchronization means are not required for such drive motors. For pulling the blind out or drawing it in, it is sufficient if an electric current of corresponding polarity is applied to the two motors simultaneously. The normal synchronism of permanent-field field d.c. motors is adequate to prevent the blind strip from being pulled a wrong direction.
The use of two motors, i.e. one electric motor for each angular gear, further permits the use of motors of smaller rating and, thus, smaller size so that further considerable space savings can be achieved. In addition, it also is possible to accommodate the motor in an offset arrangement
A simple and very space-saving form of the angular gear is achieved through use of a worm gear. The worm gear provides the additional advantage that while having small overall dimensions it is capable of transmitting a relatively high torque. Other actuating elements may consist of one-armed levers, or even toggle levers, depending on what is more convenient for the particular application.
Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings, in which: